<template>
  <div class="component-upload-image">
    <el-upload
      :action="uploadImgUrl"
      list-type="picture-card"
      :on-success="handleUploadSuccess"
      :before-upload="handleBeforeUpload"
      :limit="limit"
      :on-error="handleUploadError"
      :on-exceed="handleExceed"
      name="file"
      :on-remove="handleRemove"
      :show-file-list="true"
      :headers="headers"
      :file-list="fileList"
      :on-preview="handlePictureCardPreview"
      :class="{ hide: this.fileList.length >= this.limit, rectangle: isRectangle }"
      :disabled="disabled"
    >
      <i class="el-icon-plus"></i>
    </el-upload>

    <!-- 上传提示 -->
    <div class="el-upload__tip" slot="tip" v-if="showTip">
      请上传
      <template v-if="fileSize">
        大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
      </template>
      <template v-if="fileType">
        格式为 <b style="color: #f56c6c">{{ fileType.join("/") }}</b>
      </template>
      <template v-if="fileHeight || fileWidth">
        尺寸为 <b style="color: #f56c6c">宽{{fileWidth?fileWidth+'px':'不限制'}},高{{fileHeight?fileHeight+'px':'不限制'}}</b>
      </template>
      的文件
    </div>

    <el-dialog
      :visible.sync="dialogVisible"
      title="预览"
      width="500px"
      append-to-body
    >
      <img
        :src="dialogImageUrl"
        style="display: block; max-width: 100%; margin: 0 auto"
      />
    </el-dialog>
  </div>
</template>

<script>
import { getToken } from "@/utils/auth";

export default {
  props: {
    value: [String, Object, Array],
    // 图片数量限制
    limit: {
      type: Number,
      default: 5,
    },
    // 大小限制(MB)
    fileSize: {
      type: Number,
      default: 5,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
      type: Array,
      default: () => ["png", "jpg", "jpeg"],
    },
    //图片尺寸限制
    fileWidth:{
        type:Number,
        default:0
    },
    fileHeight:{
        type:Number,
        default:0
    },
    // 是否显示提示
    isShowTip: {
      type: Boolean,
      default: true,
    },
    //是否长方形
    isRectangle:{
      type:Boolean,
      default:false
    },
    //是否禁用
    disabled:{
        type:Boolean,
        default:false
    }
  },
  data() {
    return {
      dialogImageUrl: "",
      dialogVisible: false,
      hideUpload: false,
      baseUrl: process.env.VUE_APP_BASE_API,
      uploadImgUrl: process.env.VUE_APP_BASE_API + "/iot/tool/upload", // 上传的图片服务器地址
      headers: {
        Authorization: "Bearer " + getToken(),
      },
      fileList: [],
    };
  },
  watch: {
    value: {
      handler(val) {
        if (val) {
          // 首先将值转为数组
          const list = Array.isArray(val) ? val : this.value.split(",");
          // 然后将数组转为对象数组
          this.fileList = list.map((item) => {
            if (typeof item === "string") {
              if (item.indexOf(this.baseUrl) === -1) {
                item = { name: this.baseUrl + item, url: this.baseUrl + item };
              } else {
                item = { name: item, url: item };
              }
            }
            return item;
          });
        } else {
          this.fileList = [];
          return [];
        }
      },
      deep: true,
      immediate: true,
    },
  },
  computed: {
    // 是否显示提示
    showTip() {
      return this.isShowTip && (this.fileType || this.fileSize);
    },
  },
  methods: {
    // 删除图片
    handleRemove(file, fileList) {
      const findex = this.fileList.map((f) => f.name).indexOf(file.name);
      if (findex > -1) {
        this.fileList.splice(findex, 1);
        this.$emit("input", this.listToString(this.fileList));
        this.$emit("change",this.listToString(this.fileList));
      }
    },
    // 上传成功回调
    handleUploadSuccess(res) {
      this.fileList.push({
        name: res.fileName,
        url: process.env.VUE_APP_BASE_API + res.fileName,
      });
      this.$emit("input", this.listToString(this.fileList));
      this.$emit("change",this.listToString(this.fileList));
      this.loading.close();
    },
    // 上传前loading加载
    async handleBeforeUpload(file) {
      let isImg = false;
      if (this.fileType.length) {
        let fileExtension = "";
        if (file.name.lastIndexOf(".") > -1) {
          fileExtension = file.name.slice(file.name.lastIndexOf(".") + 1);
        }
        isImg = this.fileType.some((type) => {
          if (file.type.indexOf(type) > -1) return true;
          if (fileExtension && fileExtension.indexOf(type) > -1) return true;
          return false;
        });
      } else {
        isImg = file.type.indexOf("image") > -1;
      }

      if (!isImg) {
        this.$message.error(
          `文件格式不正确, 请上传${this.fileType.join("/")}图片格式文件!`
        );
        return Promise.reject();
      }
      if (this.fileSize) {
        const isLt = file.size / 1024 / 1024 < this.fileSize;
        if (!isLt) {
          this.$message.error(`上传头像图片大小不能超过 ${this.fileSize} MB!`);
          return Promise.reject();
        }
      }
      if(this.fileWidth || this.fileHeight){
        const isValidSize = await this.checkImageSize(file,this.fileWidth,this.fileHeight);
        if(!isValidSize){
            this.$message.error(`上传图片不符合要求，尺寸要小于:宽${this.fileWidth?this.fileWidth+'px':'不限制'},高${this.fileHeight?this.fileHeight+'px':'不限制'}`);
            return Promise.reject();
        }
      }
      this.loading = this.$loading({
        lock: true,
        text: "上传中",
        background: "rgba(0, 0, 0, 0.7)",
      });
    },
    // 文件个数超出
    handleExceed() {
      this.$message.error(`上传文件数量不能超过 ${this.limit} 个!`);
    },
    // 上传失败
    handleUploadError() {
      this.$message({
        type: "error",
        message: "上传失败",
      });
      this.loading.close();
    },
    // 预览
    handlePictureCardPreview(file) {
      this.dialogImageUrl = file.url;
      this.dialogVisible = true;
    },
    // 对象转成指定字符串分隔
    listToString(list, separator) {
      let strs = "";
      separator = separator || ",";
      for (let i in list) {
        strs += list[i].url.replace(this.baseUrl, "") + separator;
      }
      return strs != "" ? strs.substr(0, strs.length - 1) : "";
    },
    //判断图片尺寸,TODO:需要修改成Promise处理
    checkImageSize(file, width, height) {
        return new Promise((resolve, reject) => {
            const reader = new FileReader();
            reader.readAsDataURL(file);
            reader.onload = (event) => {
            const image = new Image();
            image.src = event.target.result;
            image.onload = () => {
                const imageWidth = image.width;
                const imageHeight = image.height;
                console.log(imageWidth, imageHeight);
                let isValidSize = true;
                if (height !== 0 && imageHeight > height) {
                isValidSize = false;
                }
                if (width !== 0 && imageWidth > width) {
                isValidSize = false;
                }
                resolve(isValidSize);
            };
            image.onerror = () => {
                reject(new Error("Failed to load image"));
            };
            };
            reader.onerror = () => {
            reject(new Error("Failed to read file"));
            };
        });
    }
  },
};
</script>
<style scoped lang="scss">
// .el-upload--picture-card 控制加号部分
::v-deep.hide .el-upload--picture-card {
  display: none;
}
// 去掉动画效果
::v-deep .el-list-enter-active,
::v-deep .el-list-leave-active {
  transition: all 0s;
}

::v-deep .el-list-enter,
.el-list-leave-active {
  opacity: 0;
  transform: translateY(0);
}
.rectangle ::v-deep {
  .el-upload {
    height: 100px;
    line-height: 100px;
  }
  .el-icon-plus::before {
    font-size:18px;
  }
   .el-upload-list__item {
     height: 100px;
  }
}
</style>

